http://arstechnica.com/news.ars/post/20081120-roll-your-own-search-results-with-googles-new-searchwiki.html

Continually raising the bar on search, Google has unveiled a new feature that lets those with Google accounts massage their search results. If this is an intelligent/learning feature, chances are it will allow those of us who use Google for serious searching to bend it more to our needs — roll your own Google Scholar, for instance, geared toward searching medical or LIS literature.